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1.
BMC Public Health ; 20(1): 235, 2020 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-32059663

RESUMEN

BACKGROUND: In a previous feasibility study (APROPOS) in a single municipality of the Netherlands, we showed that a locally tailored preconception care (PCC) approach has the potential to positively affect preconceptional lifestyle behaviours. Therefore, we designed a second study (APROPOS-II) to obtain a more robust body of evidence: a larger group of respondents, more municipalities, randomization, and a more comprehensive set of (clinical) outcomes. The aim of this study is to assess the effectiveness and the implementation process of a local PCC-approach on preconceptional lifestyle behaviours, health outcomes and the reach of PCC among prospective parents and healthcare providers. METHODS: This study is an effectiveness-implementation hybrid type 2 trial. This involves a stepped-wedge cluster randomized controlled trial design aiming to include over 2000 future parents from six municipalities in the Netherlands. The intervention has a dual-track approach, focusing on both the uptake of PCC among future parents and the provision of PCC by healthcare providers. The PCC-approach consists of 1) a social marketing strategy directed towards prospective parent(s) and 2) a local care pathway to improve interdisciplinary collaboration. Data will be collected before and after the introduction of the intervention through questionnaires and medical records in each of the participating municipalities. The primary outcome of this study is change in lifestyle behaviours (e.g. folic acid use, smoking and alcohol use). Secondary outcomes are pregnancy outcomes (e.g. miscarriage, preterm birth, gestational diabetes) and the uptake of PCC. Moreover, a process evaluation will be performed, providing information on the efficacy, feasibility, barriers and facilitators regarding the implementation of the intervention. DISCUSSION: The APROPOS-II study introduces a locally tailored PCC-approach in six municipalities in the Netherlands that will contribute to the body of evidence regarding the effectiveness of PCC and its implementation. If this intervention has a positive effect on lifestyle behaviour changes, leading to improved pregnancy outcomes and the future health of prospective parents and their offspring, it could subsequently be upscaled to (inter)national implementation. TRIAL REGISTRATION: Dutch Trial register: NL7784 (Registered June 6th, 2019).


Asunto(s)
Atención Preconceptiva/métodos , Adulto , Ciudades , Femenino , Conductas Relacionadas con la Salud , Humanos , Estilo de Vida , Masculino , Países Bajos , Evaluación de Programas y Proyectos de Salud , Proyectos de Investigación , Encuestas y Cuestionarios
2.
Water Sci Technol ; 79(5): 1000-1006, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31025980

RESUMEN

In this study, the contribution of pre-treatment basins of low impact development (LID) technologies to nutrient reduction performance was evaluated by understanding the distribution of nutrient in sediments accumulated in each system. The captured sediments were mostly silt to medium sand ranging from 9% to 92% of the sediments collected. Greater average N and P concentrations were found in silt particles amounting to 345 mg/kg and 696 mg/kg, respectively compared to sand and gravel. Although, N concentrations in accumulated sediments were found to be highly variable at different particle sizes (CV: 0.24 to 0.77) compared to P concentration (CV: 0.08 to 0.36) attributed to effective P treatment mechanism through deposition compared to complex nitrogen removal mechanisms. In addition, the difference between N and P concentrations of sediments collected in the pre-treatment basins of LID technologies and in-situ soil was attributed to the continuous pollutant input to the LID technologies during storm events. The study proved that pre-treatment basins of stormwater LID technologies reinforced the nutrient removal performances through sediment retention. The findings of this research may be used to design pre-treatment basins of LID technologies considering nutrients as a limiting factor.


Asunto(s)
Sedimentos Geológicos/química , Nitrógeno/análisis , Fósforo/análisis , Lluvia , Desarrollo Sostenible , Contaminantes del Agua/análisis , Suelo , Remodelación Urbana
3.
Water Sci Technol ; 78(5-6): 1045-1053, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30339529

RESUMEN

Low impact development (LID) technologies mimic the natural water cycle through the physico-chemical and biological interactions of plants, filter media and soil, and microorganisms, thereby reducing the release of pollutants. In LID facilities, plants carry out photosynthesis, facilitate microbial growth, and uptake pollutants contained in stormwater runoff. However, de-icers (CaCl2) used to melt snow during winter slow the growth of plants and even increase plant mortality. In addition, de-icers change the soil structure, causing changes in soil content and affecting the growth of plants and microorganisms. Therefore, this study examined the effects of CaCl2 on the resistance of plants, the removal efficiency of non-point source pollutants, and water circulation. The mortality rate of the tree and shrubs caused by CaCl2 was found to be in the order of Rhododendron indicum > Spiraea prunifolia var. simpliciflora > Metasequoia glyptostroboides. For herbaceous plants, mortality rate was in the order of Pratia pedunculata > Aquilegia japonica > Tagetes erecta > Sedum makinoi aurea > Hosta longipes > Dianthus chinensis > Acorus gramineus > Liriope platyphylla. In addition, it was found that the amount of chlorophyll decreases with high concentrations of CaCl2. The findings of this research will be useful for plant selection considering CaCl2 concentrations applied to paved areas during the winter.


Asunto(s)
Cloruro de Calcio/administración & dosificación , Desarrollo de la Planta/efectos de los fármacos , Plantas/efectos de los fármacos , Clorofila/metabolismo , Fotosíntesis/efectos de los fármacos , Plantas/metabolismo , Suelo , Contaminantes del Suelo/química
4.
Water Sci Technol ; 72(10): 1747-53, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26540535

RESUMEN

The study presented the application of Stormwater Management Model (SWMM) in determining the optimal physical design properties of an established low impact development (LID) system treating road runoff. The calibration of the model was based on monitored storm events occurring from May 2010 to July 2013. It was found that the total suspended solids was highly correlated with stormwater runoff volume and dominant heavy metal constituents in stormwater runoff, such lead, zinc and copper, with a Pearson correlation coefficient ranging from 0.88 to 0.95 (P<0.05). Reducing the original ratio of the storage volume to surface area (SV/SA) of the facility and depth by 25% could match the satisfactory performance efficiency achieved in the original design. The smaller SV/SA and depth would mean a less costly system, signifying the importance of optimization in designing LID systems.


Asunto(s)
Modelos Teóricos , Purificación del Agua/métodos , Calibración , Diseño de Equipo , Metales Pesados/análisis , Lluvia , Urbanización , Purificación del Agua/instrumentación
5.
Water Sci Technol ; 72(12): 2243-50, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26676013

RESUMEN

This study was conducted to compare the treatment performance of two hybrid constructed wetlands (CWs) in treating stormwater runoff. The hybrid CWs were composed of a combination of free water surface (FWS) and horizontal subsurface flow (HSSF) CWs. Based on the results, strong correlation exists between potential runoff impacts and stormwater characteristics; however, the low correlations also suggest that not only the monitored parameters contribute to stormwater event mean concentrations (EMC) of pollutants, but other factors should also be considered as well. In the hydraulic and treatment performance of the hybrid CWs, a small surface area to catchment area (SA/CA) ratio, receiving a high concentration of influent EMC, will find it hard to achieve great removal efficiency; also a large SA/CA ratio, receiving low concentration of influent EMC, will find it hard to achieve great removal efficiency. With this, SA/CA ratio and influent characteristics such as EMC or load should be considered among the design factors of CWs. The performance data of the two CWs were used to consider the most cost-effective design of a hybrid CW. The optimum facility capacity (ratio of total runoff volume to storage volume) that is applicable for a target volume reduction and removal efficiency was provided in this study.


Asunto(s)
Lluvia , Eliminación de Residuos Líquidos/métodos , Contaminantes del Agua/metabolismo , Humedales , Biodegradación Ambiental , Análisis de la Demanda Biológica de Oxígeno , Análisis Costo-Beneficio , Lluvia/química , República de Corea , Emisiones de Vehículos/análisis , Eliminación de Residuos Líquidos/economía , Contaminantes del Agua/análisis , Purificación del Agua/economía , Purificación del Agua/métodos
6.
Tissue Antigens ; 84(2): 223-8, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24786287

RESUMEN

Inflammatory demyelinating disease (IDD), which includes multiple sclerosis (MS) and neuromyelitis optica (NMO), affects the central nervous system. Chemokine ligand 2 (CCL2/MCP-1) is considered an important contributor to the development or progression of IDD. However, genetic association studies of Asian populations are lacking. In this study, we investigated a possible association between CCL2 polymorphisms (rs1024611, rs28730833, and rs2857657) and a Korean population (178 IDD patients and 237 healthy controls) using multiple logistic regression models. However, we did not find any association, which was consistent with other studies in Caucasian populations. In conclusion, our results suggest that CCL2 variants may not contribute to the pathogenesis of IDD.


Asunto(s)
Pueblo Asiatico/genética , Quimiocina CCL2/genética , Enfermedades Desmielinizantes/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Inflamación/genética , Polimorfismo de Nucleótido Simple/genética , Adulto , Enfermedades Desmielinizantes/complicaciones , Femenino , Frecuencia de los Genes/genética , Haplotipos/genética , Humanos , Inflamación/complicaciones , Desequilibrio de Ligamiento/genética , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factores de Riesgo
7.
Water Sci Technol ; 69(12): 2460-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24960008

RESUMEN

Particulates, inorganic and toxic constituents are the most common pollutants associated with urban stormwater runoff. Heavy metals such as chromium, nickel, copper, zinc, cadmium and lead are found to be in high concentration on paved roads or parking lots due to vehicle emissions. In order to control the rapid increase of pollutant loads in stormwater runoff, the Korean Ministry of Environment proposed the utilization of low impact developments. One of these was the application of tree box filters that act as a bioretention treatment system which executes filtration and sorption processes. In this study, a tree box filter located adjacent to an impervious parking lot was developed to treat suspended solids and heavy metal concentrations from urban stormwater runoff. In total, 11 storm events were monitored from July 2010 to August 2012. The results showed that the tree box filter was highly effective in removing particulates (up to 95%) and heavy metals (at least 70%) from the urban stormwater runoff. Furthermore, the tree box filter was capable of reducing the volume runoff by 40% at a hydraulic loading rate of 1 m/day and below.


Asunto(s)
Metales Pesados/química , Lluvia/química , Reciclaje/métodos , Árboles/metabolismo , Eliminación de Residuos Líquidos/métodos , Monitoreo del Ambiente , Material Particulado , República de Corea , Remodelación Urbana , Movimientos del Agua , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos
8.
Artículo en Inglés | MEDLINE | ID: mdl-39091996

RESUMEN

INTRODUCTION: Aspirin nowadays is widely used in pregnancy, but implementation among gynecologists took nearly four decades. For a complete insight in the implementation of aspirin, community midwives are to be involved. Community midwives do not have authority to prescribe aspirin and have to refer to a general practitioner or consultant obstetrician for a prescription. METHODS: The study was an online, national pilot survey about the implementation of aspirin use during pregnancy among independently practicing community midwives consisting of 29 items with five categories: background, advising, prescribing, possible indications, and clinical practice. RESULTS: Forty-seven community midwives completed the survey between April and May 2021. All respondents had experience on advising aspirin use in pregnancy. History of preterm pre-eclampsia or HELLP syndrome was identified as a risk factor for developing utero-placental complications by 97.9% of the community midwives. Moderate risk factors in women with otherwise low-risk pregnancy were identified by >75% of the participants. Practical issues in prescribing aspirin were experienced by one-third of the respondents. Suggestions were made to obtain authority for community midwives to prescribe aspirin and improve collaboration with consultant obstetricians and general practitioners. CONCLUSIONS: Community midwives seem to be adequate in identifying risk factors for developing utero-placental complications in women with otherwise low-risk pregnancy. Practical issues for prescribing aspirin occur often. Obtaining authority for community midwives to prescribe aspirin after education should be considered and consulting a consultant obstetrician should become more accessible to overcome the practical issues. Further educating community midwives and general practitioners might improve implementation rates and perinatal outcomes.

9.
Water Sci Technol ; 67(6): 1317-23, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23508157

RESUMEN

The surface-flow constructed wetland (CW) located in Nonsan City, South Korea, and constructed as the final stage of a piggery wastewater treatment plant that aims to treat high nutrient content effluent during dry days and stormwater runoff during wet days was monitored from October 2008 to November 2011. This research investigated the seasonal nutrient uptake of plant biomass in the CW and nutrient concentration changes in each treatment region under monsoon and temperate climate conditions. Results showed that the mean total nitrogen removal during summer (June to August) was higher by 13% than in spring (March to May), while total phosphorus removal was higher by 22% in fall (September to November) than in winter (December to February). All plants in the CW reached their maximum biomass coverage and weight in summer and minimum growth in winter. The highest N and P content in plants occurred in September with 583.2 g/m(2) and August with 62.0 g/m(2), respectively. Based on the results, it is recommended that the harvesting of plants should be conducted during the time of the peak nutrient uptake and before the plants release the nutrient content back to the CW. The dependence of nutrient removal efficiency on plants is not so significant. In order to increase the nutrient removal rate by plant uptake, it is suggested that the treatment regions in the CW be covered by plants.


Asunto(s)
Biomasa , Estaciones del Año , Typhaceae/metabolismo , Purificación del Agua , Humedales , Animales , Vivienda para Animales , Porcinos , Movimientos del Agua , Calidad del Agua
10.
Water Sci Technol ; 66(4): 712-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22766857

RESUMEN

This research was conducted to investigate the phosphorus forms present in water, soil and sediment and to estimate the phosphorus mass balance in a surface flow constructed wetland (CW). Water quality and sediment samples were collected from each cell along the hydrologic path in the CW from October 2008 to December 2010. At the same time, three dominant plant species (e.g. common reed and cattails) were observed through the measurement of the weight, height and phosphorus content. Based on the results, the orthophosphate constituted 24-34% of total phosphorus in water for each cell. The overall average phosphorus removal efficiency of the CW was approximately 38%. The average inflow and outflow phosphorus loads during the monitoring period were 1,167 kg/yr and 408 kg/yr, respectively. The average phosphorus retention rate was 65%, was mainly contributed by the settling of TP into the bottom sediments (30%). The phosphorus uptake of plants was less than 1%. The estimated phosphorus mass balance was effective in predicting the phosphorus retention and release in the CW treating wastewater. Continuous monitoring is underway to support further assessment of the CW system and design.


Asunto(s)
Magnoliopsida/metabolismo , Fósforo/análisis , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis , Humedales , Adsorción , Crianza de Animales Domésticos , Animales , Sedimentos Geológicos/análisis , Magnoliopsida/química , Fósforo/química , Fósforo/metabolismo , Porcinos , Movimientos del Agua , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo
11.
Water Sci Technol ; 65(1): 119-26, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22173415

RESUMEN

The efficiency of a free water surface flow constructed wetland (CW) in treating agricultural discharges from stream was investigated during storm and non-storm events between April and December, 2009. Physico-chemical and water quality constituents were monitored at five sampling locations along the flow path of the CW. The greatest reduction in pollutant concentration was observed after passing the sedimentation zone at approximately 4% fractional distance from the inflow. The inflow hydraulic loading, flow rates and pollutant concentrations were significantly higher and variable during storm events than non-storm (baseflow) condition (p <0.001) that resulted to an increase in the average pollutant removal efficiencies by 10 to 35%. The highest removal percentages were attained for phosphate (51 ± 22%), ammonium (44 ± 21%) and phosphorus (38 ± 19%) while nitrate was least effectively retained by the system with only 25 ± 17% removal during non-storm events. The efficiency of the system was most favorable when the temperature was above 15 °C (i.e., almost year-round except the winter months) and during storm events. Overall, the outflow water quality was better than the inflow water quality signifying the potential of the constructed wetland as a treatment system and capability of improving the stream water quality.


Asunto(s)
Eliminación de Residuos Líquidos/métodos , Contaminantes del Agua/análisis , Purificación del Agua/métodos , Humedales , Agricultura , Análisis de la Demanda Biológica de Oxígeno , Carbono/análisis , Concentración de Iones de Hidrógeno , Corea (Geográfico) , Nitratos/análisis , Nitrógeno/análisis , Oxígeno/análisis , Fosfatos/análisis , Fósforo/análisis , Compuestos de Amonio Cuaternario/análisis , Lluvia , Ríos , Calidad del Agua , Abastecimiento de Agua
12.
Water Sci Technol ; 66(9): 1950-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22925868

RESUMEN

Constructed wetlands (CWs) are well recognized as having low construction and maintenance cost and low energy requirement. However, CW design has been mainly based on rule-of-thumb approaches. In this study, the efficiency of a modular horizontal subsurface flow (HSSF) CW using four different design schemes was investigated. Based on the results, the four systems have attained more than 90% removal of total suspended solids and more than 50% removal efficiency for total phosphorus, PO(4)-P and Zn. The planted system achieved higher pollutant removal rates than the unplanted system. In terms of media, bottom ash was more effective than woodchip in reducing the pollutants. Considering the flow length, optimum removal efficiency was achieved after passing the sedimentation tank and vertical media layer; with respect to depth, more pollutants were removed in the upper sand layer than in the lower gravel layer. This study recommended a surface area of 0.25 to 0.8% of catchment area for planted CW and 0.26 to 0.9% for unplanted CW using the 7.5 to 10 mm design rainfall.


Asunto(s)
Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Contaminantes Químicos del Agua/química
13.
Water Sci Technol ; 65(3): 525-32, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22258685

RESUMEN

This study reported the efficiency of a free water surface flow constructed wetland (CW) system that receives runoff impacted stream water from a forested and agricultural watershed. Investigations were conducted to examine the potential effect of hydraulic fluctuations on the CW as a result of storm events and the changes in water quality along the flow path of the CW. Based on the results, the incoming pollutant concentrations were increased during storm events and greater at the near end of the storm than at the initial time of storm. A similar trend was observed to the concentrations exiting the CW due to the wetland being a relatively small percentage of the watershed (<0.1%) that allowed delays in runoff time during storm events. The concentrations of most pollutants were significantly reduced (p < 0.05) except for nitrate (p = 0.5). Overall, this study suggests that the design of the system could feasibly function for the retention of most pollutants during storm events as the actual water quality of the outflow was significantly better by 21-71% than the inflow and the levels of pollutants were reduced to appreciable levels.


Asunto(s)
Ríos/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Humedales , Agricultura , Monitoreo del Ambiente , Arquitectura y Construcción de Instituciones de Salud , Factores de Tiempo , Árboles
14.
Ultrasound Obstet Gynecol ; 37(3): 324-7, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20812377

RESUMEN

OBJECTIVE: To examine the diagnostic precision of ultrasound examination for placenta accreta in women with placenta previa and to compare the morbidity associated with accreta to that of previa alone. METHODS: This was a retrospective cohort study of all women with previa with/without accreta examined at the University of California, San Francisco (UCSF) between 2002 and 2008. The sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of ultrasound examination for the diagnosis of accreta were calculated and compared with results from similar studies in the literature. Univariable analysis was used to compare clinical outcomes. RESULTS: The PPV of an ultrasound diagnosis of accreta was 68% and NPV was 98%. Ultrasound had a sensitivity of 89.5%. Compared with previa alone, accreta had an odds ratio (OR) of 89.6 (95% CI, 19.44-412.95) for estimated blood loss > 2 L, an OR of 29.6 (95% CI, 8.20-107.00) for transfusion and an OR of 8.52 (95% CI, 2.58-28.11) for length of hospital stay > 4 days. CONCLUSION: Placenta accreta is associated with greater morbidity than is placenta previa alone. Ultrasound examination is a good diagnostic test for accreta in women with placenta previa. This is consistent with most other studies in the literature.


Asunto(s)
Cesárea Repetida/efectos adversos , Placenta Accreta/diagnóstico por imagen , Placenta Previa/diagnóstico por imagen , Hemorragia Posparto/diagnóstico por imagen , Estudios de Cohortes , Femenino , Humanos , Histerectomía , Placenta Accreta/etiología , Placenta Previa/etiología , Hemorragia Posparto/etiología , Valor Predictivo de las Pruebas , Embarazo , Estudios Retrospectivos , Factores de Riesgo , San Francisco , Sensibilidad y Especificidad , Ultrasonografía Prenatal/métodos
15.
Water Res X ; 13: 100117, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34585132

RESUMEN

Biofouling is one of the major factors causing decline in membrane performance in reverse osmosis (RO) plants, and perhaps the biggest hurdle of membrane technology. Chemical cleaning is periodically carried out at RO membrane installations aiming to restore membrane performance. Typical cleaning agents used in the water treatment industry include sodium hydroxide (NaOH) and hydrochloric acid (HCl) in sequence. Rapid biofilm regrowth and related membrane performance decline after conventional chemical cleaning is a routinely observed phenomenon due to the inefficient removal of biomass from membrane modules. Since extracellular polymeric substances (EPS) make up the strongest and predominant structural framework of biofilms, disintegration of the EPS matrix should be the main target for enhanced biomass removal. Previously, we demonstrated at lab-scale the use of concentrated urea as a chemical cleaning agent for RO membrane systems. The protein denaturation property of urea was exploited to solubilize the proteinaceous foulants, weakening the EPS layer, resulting in enhanced biomass solubilization and removal from RO membrane systems. In this work, we investigated the impact of repeated chemical cleaning cycles with urea/HCl as well as NaOH/HCl on biomass removal and the potential adaptation of the biofilm microbial community. Chemical cleaning with urea/HCl was consistently more effective than NaOH/HCl cleaning over 6 cleaning and regrowth cycles. At the end of the 6 cleaning cycles, the percent reduction was 35% and 41% in feed channel pressure drop, 50% and 70% in total organic carbon, 30% and 40% in EPS proteins, and 40% and 66% in the peak intensities of protein-like matter, after NaOH/HCl cleaning and Urea/HCl cleaning, respectively. 16S ribosomal RNA (rRNA) gene sequencing of the biofilm microbial community revealed that urea cleaning does not select for key biofouling families such as Sphingomonadaceae and Xanthomonadaceae that are known to survive conventional chemical cleaning and produce adhesive EPS. This study reaffirmed that urea possesses all the desirable properties of a chemical cleaning agent, i.e., it dissolves the existing fouling layer, delays fresh fouling accumulation by inhibiting the production of a more viscous EPS, does not cause damage to the membranes, is chemically stable, and environmentally friendly as it can be recycled for cleaning.

16.
AJNR Am J Neuroradiol ; 41(9): 1718-1725, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32816765

RESUMEN

BACKGROUND AND PURPOSE: Posterior fossa tumors are the most common pediatric brain tumors. MR imaging is key to tumor detection, diagnosis, and therapy guidance. We sought to develop an MR imaging-based deep learning model for posterior fossa tumor detection and tumor pathology classification. MATERIALS AND METHODS: The study cohort comprised 617 children (median age, 92 months; 56% males) from 5 pediatric institutions with posterior fossa tumors: diffuse midline glioma of the pons (n = 122), medulloblastoma (n = 272), pilocytic astrocytoma (n = 135), and ependymoma (n = 88). There were 199 controls. Tumor histology served as ground truth except for diffuse midline glioma of the pons, which was primarily diagnosed by MR imaging. A modified ResNeXt-50-32x4d architecture served as the backbone for a multitask classifier model, using T2-weighted MRIs as input to detect the presence of tumor and predict tumor class. Deep learning model performance was compared against that of 4 radiologists. RESULTS: Model tumor detection accuracy exceeded an AUROC of 0.99 and was similar to that of 4 radiologists. Model tumor classification accuracy was 92% with an F1 score of 0.80. The model was most accurate at predicting diffuse midline glioma of the pons, followed by pilocytic astrocytoma and medulloblastoma. Ependymoma prediction was the least accurate. Tumor type classification accuracy and F1 score were higher than those of 2 of the 4 radiologists. CONCLUSIONS: We present a multi-institutional deep learning model for pediatric posterior fossa tumor detection and classification with the potential to augment and improve the accuracy of radiologic diagnosis.


Asunto(s)
Aprendizaje Profundo , Interpretación de Imagen Asistida por Computador/métodos , Neoplasias Infratentoriales/clasificación , Neoplasias Infratentoriales/diagnóstico por imagen , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Neoplasias Infratentoriales/patología , Imagen por Resonancia Magnética/métodos , Masculino , Adulto Joven
17.
Theriogenology ; 69(8): 1001-6, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18358524

RESUMEN

We successfully produced second-generation cloned cats by somatic cell nuclear transfer (SCNT) using skin cells from a cloned cat. Skin cells from an odd-eyed, all-white male cat (G0 donor cat) were used to generate a cloned cat (G1 cloned cat). At 6 months of age, skin cells from the G1 cloned cat were used for SCNT to produce second-generation cloned cats. We compared the in vitro and in vivo development of SCNT embryos that were derived from the G0 donor and G1 cloned donor cat's skin fibroblasts. The nuclei from the G0 donor and G1 cloned donor cat's skin fibroblasts fused with enucleated oocytes with equal rates of fusion (60.7% vs. 58.8%, respectively) and cleavage (66.3% vs. 63.4%). The 2-4-cell SCNT embryos were then transferred into recipients. One of the five recipients of G0 donor derived NT embryos (20%) delivered one live male cloned kitten, whereas 4 of 15 recipients of the G1 cloned donor cat derived NT embryos (26%) delivered a total of seven male second-generation cloned kittens (four live kittens from one surrogate, plus two stillborn kittens, and one live kitten that died 2d after birth from three other surrogate mothers). The four second-generation cloned kittens from the same surrogate all had a white coat color; three of the four second-generation cloned kittens had two blue eyes, and one of the second-generation cloned kittens had an odd-eye color. Despite low cloning efficiency, cloned cats can be used as donor cats to produce second-generation cloned cats.


Asunto(s)
Gatos/fisiología , Clonación de Organismos/veterinaria , Transferencia de Embrión/veterinaria , Técnicas de Transferencia Nuclear/veterinaria , Animales , Animales Recién Nacidos , Gatos/genética , Clonación de Organismos/métodos , Transferencia de Embrión/métodos , Femenino , Masculino , Embarazo
18.
J Neural Eng ; 15(1): 013002, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29076455

RESUMEN

OBJECTIVE: There have been remarkable advances over the past decade in neural prostheses to restore lost motor function. However, restoration of somatosensory feedback, which is essential for fine motor control and user acceptance, has lagged behind. With an increasing interest in using electrical stimulation to restore somatosensory sensations within the peripheral (PNS) and central nervous systems (CNS), it is critical to characterize the percepts evoked by electrical stimulation in a standardized manner with a validated psychometric questionnaire. This will allow comparison of results from applications at various nervous system levels in multiple settings. APPROACH: We compiled a summary of published reports of somatosensory percepts that were elicited by electrical stimulation in humans and used these to develop a new psychometric questionnaire. RESULTS: This new questionnaire was able to characterize subjective evoked sensations with good test-retest reliability (Spearman's correlation coefficients ranging 0.716 ⩽ ρ ⩽ 1.000, p ⩽ 0.005) in 13 subjects receiving stimulation through neural implants in both the CNS and PNS. Furthermore, the new questionnaire captured more descriptors (M = 2.65, SD = 0.91) that would have been missed by being categorized as 'other sensations', using a previous questionnaire (M = 1.40, SD = 0.77, t(12) = -10.24, p < 0.001). Lastly, the new questionnaire was able to capture different descriptors within subjects using different patterns of electrical stimulation (Wilk's Lambda = 0.42, F(3, 10) = 4.58, p = 0.029). SIGNIFICANCE: This new somatosensory psychometric questionnaire will aid in establishing consistency and standardization of reporting in future studies of somatosensory neural prostheses.


Asunto(s)
Prótesis Neurales/normas , Corteza Somatosensorial/fisiología , Encuestas y Cuestionarios/normas , Estimulación Eléctrica/métodos , Potenciales Evocados Somatosensoriales/fisiología , Humanos , Prótesis Neurales/psicología , Psicometría
19.
Sci Rep ; 8(1): 11639, 2018 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-30076314

RESUMEN

Microplastic is a contaminant of concern worldwide. Rivers are implicated as major pathways of microplastic transport to marine and lake ecosystems, and microplastic ingestion by freshwater biota is a risk associated with microplastic contamination, but there is little research on microplastic ecology within freshwater ecosystems. Microplastic uptake by fish is likely affected by environmental microplastic abundance and aspects of fish ecology, but these relationships have rarely been addressed. We measured the abundance and composition of microplastic in fish and surface waters from 3 major tributaries of Lake Michigan, USA. Microplastic was detected in fish and surface waters from all 3 sites, but there was no correlation between microplastic concentrations in fish and surface waters. Rather, there was a significant effect of functional feeding group on microplastic concentration in fish. Neogobius melanostomus (round goby, a zoobenthivore) had the highest concentration of gut microplastic (19 particles fish-1) compared to 10 other fish taxa measured, and had a positive linear relationship between body size and number of microplastic particles. Surface water microplastic concentrations were lowest in the most northern, forested watershed, and highest in the most southern, agriculturally dominated watershed. Results suggest microplastic pollution is common in river food webs and is connected to species feeding characteristics. Future research should focus on understanding the movement of microplastic from point-source and diffuse sources and into aquatic ecosystems, which will support pollution management efforts on inland waters.


Asunto(s)
Ecosistema , Peces/fisiología , Plásticos/efectos adversos , Contaminantes Químicos del Agua/toxicidad , Animales , Monitoreo del Ambiente , Agua Dulce/química , Humanos , Lagos/química , Ríos/química
20.
Meat Sci ; 77(2): 257-63, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22061598

RESUMEN

Marbling score (MS) is the major qualitative trait that affects carcass quality in beef cattle. In this study, we examined the association between genetic polymorphisms of the titin-cap gene (TCAP) and carcass traits in Korean native cattle (also known as Hanwoo). By direct DNA sequencing in 24 unrelated Korean cattle, we identified five sequence variants in 1.2kb of TCAP. Among them, four common polymorphic sites were selected for genotyping in the beef cattle (n=437). Pair-wise linkage analysis with four polymorphisms showed strong linkage disequilibrium (LD), and three major haplotypes (freq.>0.1) were constructed. Statistical analysis revealed that polymorphisms in intron1 (g.346G>A) and exon2 (g.592-597CTGCAG[Leu-Gln]insdel) showed significant association with marbling score (P(cor.)=0.003 and 0.02, respectively). One haplotype, ht2[C-G-G-del], also showed significant association with MS (P(cor.)=0.0004). Our findings suggest that polymorphisms in TCAP might be among the important genetic factors involved in carcass quality in beef cattle.

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